Power Analysis for an Unconditional Growth Model Using a Selected Sample

(Updated: 2020-12-31) Problem Statement Determine whether, given what we know about the target phenomenon, a sample of 120 subjects, measured at three time points is sufficient to detect linear change in an unconditional growth model. A trained phlebotomist once described her experience trying to pierce a patient’s vein with her needle as akin to “Trying to use a toothpick to stick a wet noodle covered by a piece of wax paper.

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